Double Thermostat Override Release (DTO/R) for Fire/Smoke Dampers

DTO/R Package - Double Thermostat Override Release

Prior to today’s advancements in smoke tion fire/smoke dampers may need to oper- mum design limit. The DTO/R options also control techniques, fan systems were re- ate at temperatures above and beyond their permits a combination fire/smoke damper quired to shut down during fire conditions initial closure rating. PRICE’s DTO/R option to be reopened after a fire emergency has and fire dampers were closed by heat. Air provides the capability to override rated been controlled providing the temperatures pressures were not utilized for the control damper closure from a secure remote loca- at the damper have cooled down below the and containment of smoke. In recent years, tion (such as a fire fighter’s smoke control maximum design limit. Please note that the the requirement that systems completely station). Upon sensing temperature above DTO/R option is recommended only for use shut down and fire dampers close and re- the initial rating (usually 165°F or 212°F) the in systems utilizing an Engineered Smoke main closed during fire conditions has been damper will close but it may be reopened at Control design. questioned. With the current engineered the command of a remotely located control The DTO/R option is available on all PRICE smoke control systems simple closure of a to permit utilization of the HVAC/Engineered Model FSD Combination Fire/Smoke fire damper at a specific temperature is no Smoke Control System, but only until such Dampers. longer the absolute requirement. Combina- time as the fire conditions exceed the maxi-

FSD DAMPER DTO/R OPERATION Indicator Switch Electrical Limitations Manufacturer’s Recommendations Switch is in Normal (Open) Position damper • 10 Amperes, 1/4 HP, 120 or 240 Volts All moving parts of the damper must be motor is energized until thermostat senses A.C. inspected and cycled at intervals not greater temperature above initial closure rating. • .5 Ampere, 125 Volts D.C. than every six months and in accordance Above temperature closure rating, the • .25 Ampere, 250 Volts D.C. with the latest edition of NFPA 90A, 92A, damper motor is de-energized and damper local codes and the actuator manufacturer. closes. • 5 Amperes, 120 Volts (Lamp Load) In addition, fuse links shall be removed and Switch may then be moved to the Override • 15 Amperes, 24 Volts D.C. inspected for corrosion. Dry lubricants are Position and the damper will reopen and recommended. remain open until maximum operating temperature is reached. Once this temperature has been reached the damper motor is de- energized and the damper closes. Switch in Closed Position damper motor is de-energized and damper is closed. Detailed wiring diagrams including termi- nal designation and/or wire color coding furnished with each shipment.

All Metric dimensions ( ) are soft conversion. © Copyright E.H. Price Limited 2006. Jul / 06 245083 SHEET 1 OF 2 Imperial dimensions are converted to metric and rounded to the nearest millimetre. Double Thermostat Override Release (DTO/R) for Fire/Smoke Dampers

DTO/R Package - Double Thermostat Override Release